Scientists have provided the first direct biological evidence for a genetic contribution to people’s intelligence.
Previous studies on twins and adopted people suggested that there is a substantial genetic contribution to thinking skills.
The University study is the first to test people’s DNA for genetic variations, linked to intelligence.
The team studied two types of intelligence in more than 3,500 people from Scotland, England and Norway.
They found that 40 per cent to 50 per cent of people’s differences in knowledge and problem solving skills could be traced to their genes.
The study examined over half a million genetic markers on every person’s DNA.
The findings were made possible using a new type of analysis invented by Professor Peter Visscher and colleagues in the Queensland Institute of Medical Research, Brisbane.
We have found genetic signals associated with people’s intelligence differences. We have not found the actual genetic differences that cause some intelligence differences, but we now have evidence that some of the genetic causes are linked to those genetic factors that we tested. This gives us leads that we are now planning to follow.
The findings have been reported in the journal Molecular Psychiatry. The paper was authored by Gail Davies and colleagues from the School of Philosophy, Psychology and Language Sciences.
Professor Neil Pendleton from the University of Manchester was also part of the research team.